The present invention relates to the use of a hydrogen peroxide and peracetic acid based disinfectant which is capable of eliminating parasite microorganisms that affect fish fauna, no matter whether it be in fresh or sea water.
The product according to the present invention is particularly suitable for the fish industry and in the fish growing field thereto related.
It is known that fish fauna, including heretofore both fresh water fish (such as eel, trout, and so on) and sea water fish (such as bass, dory, salmon, an so on), is often subject to the aggression of numerous microorganisms.
Infective and infestive pathology control on fish results to be extremely delicate and of paramount importance, mostly in the fish growing field, where considerable interests of economic nature are at stake.
It is known that some microorganisms find a dwelling and a source of nourishment inside the body of a fish, and, in order to be able to suppress said microorganisms, it is necessary to treat ill fish with specific antibiotics and chemiotherapeutics.
This means therefore that in order to obtain the eradication of these microorganisms, it is necessary to make fish undergo treatments with specific antibiotics administered in suitable doses.
On the other hand, if externally dwelling microorganisms are involved, these act and survive by attaching onto the hosting fish""s skin, choosing particularly favorable sites of it, like for example near the tail or gills where they can objectively find a valid docking point and source of food for their survival.
Among said microorganisms are for example Ichthyophthirius sp., Tricodina sp., Costia sp., Mixobacteria, eel, trout and fresh water fish Saprolegna, xe2x80x9csea-licexe2x80x9d for sea water fish.
As these external microorganisms locate themselves on the skin of the fish that they find to be most suitable for them, their spreading amongst individuals belonging to the same group and/or environment results to be extremely simple and easy to occur, because of the frequent skin to skin contacts that do make it possible for the transfer of said external microorganisms to take place from an ill individual to a healthy one.
The technology currently employed for the suppression and/or detachment of said microorganisms involves the emplyment of disinfectants to be mixed with water in manners determined by whether environmental water has a low exchange rate, like for example that of a fish breeding plant, or a high one like that of a river, or that of a large or small volume of sea or of a lake basin.
In trout-growing for example, disinfectants are diluted in the water of the fish breeding plant so as to carry out both preventive and therapeutical treatments on adult fish and on their eggs in order to fight against particular forms of mycosis.
A particularly risky period is for example that of the pressing season because the handling and the stress from capture that fish are forced to undergo cause skin lesions on them together with the alteration of the protective phlegm present on their skin, thus favoring the occurrence of Saprolegnosis.
Among the disinfectants employed for parasite infestation control and against the external protozoans mentioned above, are for example formalin, copper sulphate, potassium permanganate, malachite green, chloramine T., sodium chloride, etcetera.
The main drawback of most of the disinfectants traditionally employed in order to suppress the microorganisms that affect fish fauna is represented by the fact that some of these are carcinogenic, and as such they are prohibited in compliance with the current special laws in force, or they are strongly suspected to be so.
A further more than slightly remarkable disadvantage of many disinfectants, such as for example formalin, is given by the environmental impact that they have because of their toxicity, mostly in areas where waste waters from fish growing farms are disposed of.
Many of such products are in fact not environmentally friendly and as a consequence of that there is the damage they cause on the natural environment where fish subjected to such treatments live, furthermore causing often irreparable damage to the flora and fauna present therein.
In so far as the employment of sodium chloride is concerned on the other hand, problems are essentially related to storage and transport of the product as very large amounts and volumes of it have to be used.
Furthermore it is known in the art that (reference is for example made to document U.S. Pat. No. 5,313,911) the employment of suitable concentrations of hydrogen peroxide as an antiparasite agent is advantageously viable against salmon louse (Lepeophtheirus Salmonis).
According to what disclosed in the above mentioned patent, hydrogen peroxide concentration is generally in the range between 1.2 and 5 g/l; moreover, that document discloses how it is possible to accomplish an optimum result, with a success percentage in the 100% range, and keeping hydrogen peroxide concentration around 1.5 g/l for a time lapse which is longer than 20 minutes.
The employment of peracetic acid is further known as a disinfectant which is traditionally employed for the disinfection of different types of premises and appliances.
For example, peracetic acid is advantageously employed in the zootechnic field for the disinfection of premises, fodder and bedsteads; in the agriculture and food fields for the disinfection of containers generally used in the beer, wine and milk and cheese industries; in the field of recycling and purifying water for human consumption; in the municipal and industrial waste liquid biological oxidation plants.